Movable piston means for retaining fluid in electrical coupling device



Aug, 12, 1969 G. aRocKHAus ETAL. 3,461,257

MOVABLE PISTON MEANS FOR RETAINING FLUIDN ELECTRICAL COUPLING DEVICE Original Filed May 26, 1965 United States Patent O Int. Cl. H01h 33/68,33/82; H01r 13/70 U.S. Cl. 200-150 4 Claims ABSTRACT OF THE DISCLOSURE The invention relates to a high tension coupling having a fixed electrical contact in a closed chamber filled with a uid insulation, a movable piston carrying another electrical contact and arranged in said chamber to retain the fluid therein. Exteriorly of the chamber there is provided a reciprocable element which carries a still further electrical contact which upon movement thereof relative to the other contacts engages and moves the piston-carried contact whereupon all of the respective contacts are brought into engagement.

This application is a divisional application of our copending application Ser. No. 458,982, iiled May 26, 1965, now Patent No. 3,374, 331, entitled Electrical Conductor.

This invention relates to improvements in coupling means for high tension conductors and, more particularly, conductors of the type which are completely immersed in an insulation medium such as oil, non-conductive gas, cast resin, or the like, the insulant being contained in a grounded envelope.

It is presently known to provide high-tension conductors of this general type which may be positioned close to similar elements that are at a different potential and they, therefore, permit installations for high voltages to be compactly designed. Diiculties arise, however, where mobile components of installations, such as mobile trucks containing power-circuit breakers, are required to be connected Or disconnected to the system under potential. r[he connection and disconnection of such insulated conductors, when carrying voltages of 100 kv. or at even higher voltages, have been impossible with conventional coupling and uncoupling means when the spacing of conductors is reduced to take full advantage of the efficiency of this kind of insulation.

Thus, the invention has among its objects to provide a coupling for high tension conductors of the type referred to by the use of which the above-mentioned diiculties can be easily avoided.

According to the invention, there is provided a coupling for high tension conductors which are immersed in an insulating medium -with the coupling including contact members that are adapted to be disengaged in a substantially permanently closed casing filled with an insulating medium, and from which no significant quantities of the insulating medium can escape and within which casing disengagement of the high tension conductors takes place before the conductor insulation is separated and a break in the air is formed and wherein the contacts are not re-engaged until the air break and the conductor insulation have lirst been closed.

In a coupling of this type the described sequence of operations may be automatically performed when the coupling members are pushed together or pulled apart.

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Furthermore, in such a coupling the conductor insulant may be a solid, a liquid, or a gas, and it is unimportant whether the insulant is in any one of these mediums provided the insulant in the casing wherein the engagement and disengagement takes place is filled with a luid medium. Of utmost importance is the fact that the engaging and disengaging operation is effected between solid walls so that no insulation medium can escape.

The construction taught herein, it will be observed, can be made so that the casing, together with the auxiliary spacer gap, form one movable wall which is provided with diametrically disposed contact pieces adapted to be interconnected on the inside of the casing as well as the outside thereof, through the medium of another contact member interposed between the first contact piece positioned in the casing and a secondary movable contact, the elements being so arranged that when coupling is to be achieved, the insulant which is displaced from within on the casing is forced into an accumulator that is positioned over a perforation in an aperture in the casing, and subsequently returned to the casing upon Withdrawal or disconnection of the last named contact. The accumulator can be constructed in the form of a cylinder provided with a reciprocable piston, as shown, or a bellows or invertible sleeve.

Thus, according to the principle object of this invention, there is provided an improved high tension coupling means in which at least one electrical contact is positioned in a closed insulation-lilled chamber with access to the chamber being gained by a means positioned exteriorly thereof which Supports another electrical contact means.

Another object of the invention is to provide an improved valve and operating means therefor which permits the making and breaking of the electrical contacts without loss of the insulation medium.

A further object of the invention is to include as a part of the closed chamber or casing an improved accumulator or storage chamber for the displaced insulant.

Another object of the invention is to provide intermediately disposed electrical contact means movably mounted in the insulant-filled chamber.

A still further object of the invention is to provide a linkage means which, upon actuation by the second electrical contact means, oscillates the valving means into an inoperative position, thereby permitting coupling of the contacts.

Yet another object of the invention is to provide a slidable orifice valve in one wall of the insulant chamber, the orifice valve being capable of lateral movement to longitudinally align the cooperating electrical contacts when they are moved relatively toward each other.

Other objects and advantages will become apparent upon a further reading of the following detailed description taken in conjunction with the drawings, in which:

FIG. 1 is a cross-sectional elevational view of one embodiment of a coupling illustrating the contacts in disengaged position;

FIG. 2 is a cross-sectional elevational view of the coupling of this embodiment of the invention shown in fully engaged circuit-making relation; and

FIG. 3 is a cross-sectional elevational view of another expansible container.

Turning now to the drawings, and more particularly to FIG. 1, a first electrical conductor 10 is connected to a bus-bar system (not shown). This conductor 10 is embedded in a cast resin envelope 11 that is telescoped by a metal sheath 12 and projects downwardly therefrom into the casing 13 which is filled with oil, or an insulating gas, such as sulfahexafluoride. Positioned at the free end of the first electrical conductor 10i, which projects from the cast resin envelope, is a contact 14 which is shown in elevation. One portion of the wall of the casing 13 is apertured as at 15, iianged as shown and adapted to receive a cylinder 16 which contains a piston 17 preloaded by a spring 18. The casing 13 is provided with an annular inturned flange portion 20t which is adapted to be received on an outwardly projecting annular ledge portion 21 which is integrated into a grounding tubular means 22 within which is positioned a generally tubular hollow cast resin body 23. The hollow cast resin body 23 is provided with a central aperture extending therethrough and adapted at its upper portion to telescope a metallic cylinder member 24 which is provided at its lowermost extremity with an inturned annular shelf portion 25 which is adapted to receive a piston member or other valving means 26 which is adapted to movably support an electrical contact member 27. It is to be noted that the upper extremity of the contact member 27 is provided with a plurality of contact fingers 28 which are adapted to be received within complemental contact means provided within the element 14.

Beneath the piston 26 and arranged to be movably supported thereby is another contact member 29 which is also shown in elevation, this contact member being open to the atmosphere. Contact member 29 is provided in its lower surface with a series of electrical contacts (not shown) within which the plurality of contact lingers 30, supported on the carrier 31, are adapted to project the last named carrier being positioned on the extremity of a conductor 32 carried by a piece of mobile equipment.

Referring now to FIG. 2, it will be noted that the carrier 32, which extends through a cast resin member 33 the intermediate portion of its longitudinal extremity being provided with a metallic sleeve 34, has together therewith been moved into a fully engaged contacting position. The sleeve 34 is provided with an annular outturned perforated flange 35 to which is secured an inverted substantially frusto-conical cup-shaped plastic mem-ber 36, the lower inturned annular perforated flange portion of which is suitably secured to the perforated flange 35. It will be noted that the interior diverging wall of the cast resin body 23 is substantially truste-conical and complementally formed to the perimeter of the frustoconical plastic sleeve 36. As indicated by the arrows 37, the interior of the plastic sleeve 36 can be pressurized by the introduction thereinto of a gas through the coincident apertured flanges, as described, thereby moving the plastic sleeve 36 into firm engagement with the internal frusto-conical face of the cast resin body 23 and aligning all of the series of contact elements into fully engaged position, as shown.

The elements 38 and 39 are the only portions represented of a piece of mobile equipment which may be, for example, a truck for a retractable power circuit breaker, these parts being mounted thereon. When the electric circuit breaker is to be disengaged, these elements are moved downwardly together with the conductor 32 and as a consequence, the piston 26 and contact carrier member 27 are lowered into a disengaged position and at which time the preloaded piston 17 is forced by means of spring 18 into its position as shown in FIG. 1 which assists in breaking the contact between elements 14 and 28 and thereby returning the piston 26 to its lowermost position as shown in FIG. 1.

As is obvious from a study of these drawings, the disengagement of contacts 14 and 28 occurs inside the insulating medium within the casing 13. IDuring the course of the further retraction of the contact carrier means 32, the contacts 29 and 31 are fully disengaged. In order to completely disengage all the contacts thereby moving the telescoped sleeve 34 downwardly within elements 38 and 39, the pressure medium, as shown as being applied at 37, must be released.

When the coupling is disengaged, the piston 17 is displaced by the preloaded spring 18, to the left as viewed in FIG. 1, and pis-ton 26 moves downwardly; thus contact 14, which carries the potential remains completely immersed in the insulating medium in the casing 13 and does not come into contact with the ambient air. When the coupling is to be re-engaged, `the described sequence of events proceed in the reverse order.

In FIG. 3 there is shown another type of expansible storage container, indicated as 40, into which any incompressible medium, such as oil, can be transmitted upon upward movement of piston 26.

That which is claimed is:

.1. A high tension coupling means comprising, a rst closed chamber filled with a uid insulation, movable piston means in said chamberV to retain the Huid in said first chamber during circuit-making and circuit-breaking operations, said piston including first contact means, a second electrical contact element in said closed chamber in substantial alignment with said contact means on said piston means, reciprocable means positioned exteriorly of said chamber supporting a third electrical contact means which, upon movement thereof relative to said first contact, engages and moves the piston means carrying said lirst contact means, whereby engagement of the respective contacts is initiated.

2. A high tension coupling means as claimed in claim 1, wherein the first closed chamber is provided with an expansible storage container means adapted to receive a portion of the tluid from said first chamber when the respective contacts are engaged.

3. A high tension coupling means as claimed in claim 2, wherein the expansible storage container means comprises a cylinder, second piston means in said cylinder and resilient means between said cylinder and piston means.

4. A high tension coupling means as claimed in claim 2, wherein the expansible storage container means comprises a bellows.

References Cited UNITED STATES PATENTS 1,706,140 3/ 1929 Brand 20G- 150 1,945,916 2/ 1934 Rump et al.

2,224,611 12/ 1940 Skeats 200-150 2,389,346 11/ 1945 Denault 20G-150 2,396,871 3/ 1946 Meyerhans 20G-148 XR 2,757,261 7/ 1956 Lingal et al. 20G-148 3,002,073 9/ 1961 Cobine.

3,250,869 5/1966 Link 200-51 FOREIGN PATENTS 607,795 1/ 1935 Germany.

iROBERT S. MACON, Primary Examiner U.S. Cl. X.R. 20G-51, 148 

